Circuit breaker



April 29 1924. 1,491,799

J. w. HAYWOOD CIRCUIT BREAKER Original Filed Avril '7. 1919 7 5 1a 5- I}? 2 1 k/ 6 a k 6 4 15 fl l5 2 19 21 17 21 24 2 1 M 1 16 L 1-4 2 9" L i s 25 52a 25 W "201 a2 3 25 25 11 31 15 l5 l1 i :1"? 28 INVENTOR s 2 Z ATTORNEY Patented Apr. 29, 1924.

UNITED STATES PATENT OFFICE.

JOHN W. HAYWOOD, OF NEW YORK, N. Y., ASSIGNOR. BY MESNE ASSIGNMENTS, T HORNE ELECTRIC & MANUFACTURING COMPANY. A CORPORATION OF NEW JERSEY.

CIRCUIT BREAKER.

Application filed April 7,1919, Serial No. 288,001. Renewed August 28, 1923.

T 0 all whom it may concern Be it known that I. JOHN HAYWOOD. a citizen of the United States. and resident of the borough of Bronx, in the county of Bronx. city and State of New York, have invented a new and useful Circuit Breaker. of which the following is a specification.

The invention is an improved automatic circuit-breaker or over-load cut-out, and comprises particularly a construction of circuit-breaker adapted for use in place of standard fuses such as are most commonly encountered in manufacturing establishments and elsewhere. The object is to provide a device which shall be small, compact. simple and eflicient for its purpose. The invention accordingly comprises the novel construction and combination of parts the pres ent preferred embodiment of which will now be described.

In the accompanying drawings forming a part hereof:

Fig. 1 is a side elevation of a fuse-form circuit-breaker, closed;

Fig. 2 is an elevation thereof, open;

' Fig. 3 is a plan or front elevation (depending upon the position assumed for the device) and Fig. 4 is an enlarged cross-section on the line 4-4 of Fig. 1.

The device has a narrow. elongated base member 1 of insulating material. This member may be flat on top and have a rounded bottom, as. shown. corresponding substantially as to length and width to the body of a fuse. On opposite ends of the insulation body are conducting ferrules 2, 3. which are preferably segmental. instead of completely circular as in a fuse. These ferrules, it will be understood. are adapted to fit ordinary fuse-clips, in the place of a fuse. the circuit-breaker, in each instance, being designed for the same duty as the fuse which it replaces.

A contact plate 4 is secured to one end of the face of the insulation body 1 by the same screw 5 which secures the ferrule 2 with which this stationary contact is accordingly electrically connected. A carbon plate 6 is secured to the outer portion of the face of the contact 4 by a screw 7. A base-piece 8, of magnetic material. is secured flat along the top or face of the insulating body or base member 1 by a screw 9. this piece preferably extending from a point near the opposite end of the body to a point about midway.

A bent bar 10 of magnetic material is pivoted at one end to what for convenience may be termed the rear end of the magnetic base-piece 8. This bar has a straight portion overhanging the base-piece and bearing a magnetizing coil 11. and a retroverted bent under tail 12, which latter is connected by the transverse pivot 13 to the end of the base-piece. 7

The breaker-arm is completed by a flexible conductor and contact-bearing extension 14. which is screwed or otherwise united to the top or back of the bar or core-portion. Said extension projects substantially straight forward from the end of the core-portion for a short distance. and is then offset toward the base by the transversely-bent intermediate region 15, from which it extends substantially straight again as seen at 16. To the under or inner side of this last portion, toward the rear thereof, is riveted a laminated contact 17, and to the outer end of it is screwed a carbon break contact 18. The forward end of the laminated contact 17 is curved downward (or inward) to bear upon the stationary contact 4. while the carbon break contact 18 co-operates with the carbon plate 6, the relations being such that, when the circuit-breaker flies open. the carbon contacts are not separated until after the main contacts have broken.

The breaker-arm is adapted to be held closed by a pivoted detent 19 of magnetic material projecting outward from the base and having a beveled latch head 20 with undercut holding shoulder 21. The latch head passes through an opening 22 in the part of the flexible extension 14 immediately in front of the forward end of the core portion 10, and co-operates with an abutment on said part in the form of a small roller 23.

'The detent is pivoted atv 24 to the forward end of the magnetic base-piece 8, being thus connected in the magnetic circuit.

The detent is pressed to holding position by a fiat spring 25. one end of which is secured to the detent and the other end of which is free and bears upon an underlying region on the base. A stop-shoulder 26 lirnits the movement of the detent under the action of the spring to such position, that when the breaker is closed from the open condition of Fig. 2 the detent will be pushed Ill back, for automatic restoring, by the camming action first of the corner 27 and then of the roller 23 upon the beveled head 20. The breaker-arm is actuated by a flat spring 28, which is secured along the base-piece S by the screw 9 at one end, and at the other end deflected so as to bear upon the inner surface of the bent-under tail 12. The under side of this tail, which in the closed condition is oblique to the base, also serves as a stop to limit the opening movement of the arm. Both springs, it will be observed, are of simple and durable character and are compactly accommodated in the space under the breaker-arm, between the tail and the detent and in such manner as to be effective in their action.

The coin 11 is connected in circuit by coil ends 30 and 31 secured, respectively, to the ferrule 3 and extension 14. The coil end 30 is of suitable flexible character.

The setting of the device can be adjusted by a screw 32 beneath the spring 25. This is useful as a factory adjustment, the kerfed end of the screw being preferably embedded as shown in Fig. 4 before the device is sent out, so that the adjustment may not be disturbed but the screw can be accessible if desired.

In use, the current flows through the coil 11, the portion 10 of the breaker-arm being insulated from the ferrule terminal 3 by the insulating base 1. The proportions of the coil and the parts of the magnetic circuit are so calculated that when the current reaches the value at which a fuse suitable for the same location would blow, the core 10 attracts the armature detent 19 against the resistance of the spring 35, whereby the arm is released, and flies open breaking the circuit. In this operation, it may be noted, the roller form of the abutment 23 on the arm is of substantial importance, in a device of this character, as otherwise it would be diflicult to make the magnet powerful enough for its duty and still keep the device within fuse proportions.

lVhile I have described the preferred embodiment of the invention in detail, it will be understood that changes in form, proportions, and details may be made without departing from essentials.

What I claim as new is:

. 1. In a circuit-breaker, the combination of a base, a swinging breaker-arm comprising a core of magnetic material, an energizing coil on the arm, and a movable detent on the base forming an armature for the core.

2. An electro-magnetic fuse comprising a narrow elongated base having terminals adapted to fit between fuse clips, and a circuit-breaker on the base connected with said terminals comprising a spring-pressed breaker-arm of magnetic material bearing a magnetizing coil in circuit between the fuse clip terminals, and a detent for the breakerarm controlled by the coil.

3. In a circuit-breaker, a swinging break-' for the breaker-arm also pivoted onthe magnetic base portion.

5. In a circuit-breaker, and in combination with a detent, a breaker arm to be restrained by said detent comprising a. core portion bearing a magnetizing coil, a flexible extension, a laminated contact united to said flexible extension, and a carbon break contact carried by the extension beyond the laminated contact.

6. In a fuse-form circuit-breaker, a narrow elongated base of insulation with forrule ends, a magnetic base piece, a magnetic breaker-arm connected to the magnetic base piece, a magnetic detent also connected to said base piece, a magnetizing coil on the breaker-arm, and springs for the arm and detent.

7 In a circuit-breaker having a base and stationary contact and a detent, a breakerarm to be restrained by said detent comprisin a core portion bearing a magnetizing c011, and a flexible extension bearing a contact and having a keeper for the detent.

8. A magnetic circuit-breaker having, in combination with a base and detent, a breaker-arm comprising a coil-bearing core portion, and a flexible extension having a keeper for the detent and beyond said keeper being offset toward the base and bearing a contact.

9. In a circuit-breaker having a base, a

breaker-arm comprising a core portion bearing a'coil and an extension bearing a contact, and a bentunder tail on the core portion pivoted to the base, a detent on the base at the forward part of the core portion, and a spring beneath the core portion bearing upon the inner surface of the tail.

10. In a circuit-breaker having a base, a coil-bearing magnetic breaker-arm having a bent-under tail pivoted on the base and cooperative therewith as a stop to limit the breaking movement, and a flat spring secured to the base beneath the arm and bearing upon the inner surface of the tail.

JOHN W. HAYWOOD. 

